In computer networks, a channel access method, or a multiple access method, allows more than two terminals connected to the same transmission medium, or communication channel, to transmit data over the medium and share the capacity of the medium. Examples of shared physical mediums are bus networks, ring networks, wireless networks, and point-to-point links operating in half-duplex mode. A channel access method is based on multiplexing that allows several data streams or signals to share the same communication channel. Terminals using the same transmission medium need to be synchronized to avoid data collisions.